Hydraulic couplers are used subsea to provide a valve-controlled connection between hydraulic lines. Normally a coupler of this kind has an elongate body with an internal longitudinal passageway which at one end is adapted for coupling to a hydraulic line and includes a valve openable on mating of the coupler with a complementary coupler to provide hydraulic communication through the passageway. Many different designs are known, and typical examples are described in for example the published International patent applications WO 2007/045811 and WO 2008/074973.
Subsea modules and other subsea equipment normally require a multiplicity of hydraulic couplers and it is customary to mount an array of such couplers on a mounting plate, often called a ‘stab’ plate. Typically female or socket couplers are mounted on one such plate whereas the male or probe couplers are mounted on another plate, the plates being closed together to effect mating of each pair of complementary couplers.
Typical designs, such as those described in the aforementioned applications, include a valve in the form of a poppet of which the nose is depressed away from a part-conical seat when the coupler is mated with a complementary coupler.
Most designs of subsea couplers have an annular shoulder which protrudes radially from the main body of the coupler and abuts against the front face of the mounting plate, and a retainer, in the form of either a nut or a washer and spring clip, which engages the body of the coupler and the rear face of the mounting plate to secure the body of the coupler in the respective aperture of the mounting plate.
Such designs of coupler can be inserted only in one direction, i.e. into the front face of the mounting plate. Some designs allow for insertion of the coupler into the mounting plate from the rear thereof but in such designs the aforementioned retainer engages the front face of the mounting plate. When hydraulic couplers are mated, owing to the normally very high pressure in the hydraulic lines, the very high separation force on the couplers is borne by the retainer.
The present exemplary embodiment concerns an improved design of coupler which can be inserted through an aperture of the mounting plate in either direction and which can readily be disposed so that the separation forces generated when the system is pressurized are not carried by the retainer.